The assignee of the present invention designs and develops electric vehicles. In pure electric vehicles, there is not internal combustion engine from which to draw motive power to a hydraulic pump of a hydraulic power steering system. One method to compensate this is to provide a motor, such as an induction motor, as the motive input. The conventional hydraulic system, though, uses mechanical or belt drive from the mechanical input and pressure sensing of the power steering system to provide feedback and control system pressure. This type of system does not provide optimum efficiency and tends to use power to keep the steering system pressurized when not utilizing the pressure to ensure that the system has desired response when a steering input is provided.
It would therefore be desirable to have an improved power steering system for use in electric vehicles. It would also be desirable to have an improved induction motor load compensation algorithm or method for use in electric vehicle power steering systems.